Folding exercise treadmill with front inclination

ABSTRACT

An exercise treadmill includes a base frame, a treadmill frame having a front side detachably connected to the base frame, a locking mechanism for locking the front side of the treadmill frame to the base frame, two wheeled crank arms pivoted to the treadmill frame, and a lifting mechanism. The lifting mechanism has a motor and a transmission unit coupled to the motor and the crank arms for lifting or lowering the front side of the treadmill frame after unlocking of the locking mechanism or for lifting or lowering a rear side of the treadmill frame after locking of the front side of the treadmill frame to the base frame by the locking mechanism.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an exercise treadmill and moreparticularly, to an exercise treadmill having a fold-up capability and afront that is adjustable in the vertical direction.

2. Description of the Related Art

A conventional exercise treadmill essentially includes a base frame anda treadmill frame. The base frame is placed on the floor, having anupright upwardly extended from the front side for holding by the userwalking on the treadmill belt of the treadmill frame. In order tosimulate walking on a slope, the treadmill frame is provided with alocating hole on the front side for connection to one of a vertical rowof locating holes at the front side of the base frame selectively by alock pin. After use, the user can lift the rear side of the treadmillframe and receive the treadmill frame to the upright of the base frameto reduce space occupation.

This manual design is suitable for a small scale exercise treadmill, notpractical for use in a big scale exercise treadmill. When received inthe non-operative position, an additional lock device is necessary tolock the treadmill frame in the received position. A mistake duringoperation may cause the treadmill frame to fall, resulting in anaccident.

SUMMARY OF THE INVENTION

It is the primary objective of the present invention to provide anexercise treadmill, which enables the treadmill frame to be received inthe non-operative position or adjusted to the desired angle ofinclination by means of an electric control.

It is another objective of the present invention to provide an exercisetreadmill, which provides a self-locking function during turning of thetreadmill frame, ensuring a safety use.

To achieve these objectives of the present invention the exercisetreadmill comprises a base frame, a treadmill frame having a front sidedetachably connected with the base frame, a locking mechanism providedat a front side of the base frame for locking the front side of thetreadmill frame to the base frame, at least one crank arm pivoted to thetreadmill frame and having a sliding member for supporting on the floor,and a lifting mechanism mounted in the treadmill frame. The liftingmechanism includes a motor, and a transmission unit coupled between themotor and the crank arm for moving the sliding member of the crank armon the floor upon operation of the motor so as to either force the frontside of the treadmill frame to move vertically relative to the baseframe while the front side of the treadmill is detached from the baseframe or force a rear side of the treadmill frame to move verticallyrelative to the base frame while the front side of the treadmill islocked to the base frame by the locking mechanism.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a top view of an exercise treadmill according to the presentinvention, wherein an upright of the base frame is not shown.

FIG. 2 is a left side view of the present invention showing thetreadmill frame set in horizontal.

FIG. 3 is similar to FIG. 2 but showing the front of the treadmill framelifted.

FIG. 4 is a left side view of the present invention showing the receivedstatus of the exercise treadmill.

FIG. 5 is a sectional view taken along line 5-5 of FIG. 1, showing thestop flange of the lock pin inserted through the locating plate; and

FIG. 6 is similar to FIG. 5 but showing the stop flange of the lock pinstopped against the stop rods of the locating plate.

DETAILED DESCRIPTION OF THE INVENTION

As shown in FIGS. 1 and 2, an exercise treadmill provided by a preferredembodiment of the present invention is shown comprised of a base frame10, a treadmill frame 20, a locking mechanism 30, two crank arms 40, anda lifting mechanism 50.

The base frame 10 is a rectangular open frame formed of metal rodmembers by welding for placing on the floor. The base frame 10 comprisesan upright 12 upwardly extended from the top near the front side forholding by the user using the exercise treadmill, a control panel 13mounted on the upright 12, a retaining member, namely a lug 14, at thefront side of the upright 12, and two upright sidewalls 15 bilaterallylongitudinally disposed at the front left and right sides. The sidewalls15 each have a vertically extended guiding slot 16 and a sliding slot 17horizontally forwardly extended from the bottom end of the guiding slot16 to the periphery of the sidewall.

The treadmill frame 20 is mounted on the base frame 10, having a frontside 21, a rear side 22, a left side 23, a right side 24, a walking belt25 provided between the left side 23 and the right side 24 for walkingby the user using the exercise treadmill, a foot member 26 at the bottomof the rear side 22 for supporting the rear side of the treadmill frame20 on the floor, a first retaining member, namely a first lug 27 havinga through hole, at the bottom of the front side 21, two second retainingmembers, namely two second lugs 28, symmetrically disposed at the leftside 23 and the right side 24 and connected with each other by a rod 28a, two locating rods 29 respectively outwardly protruded from the leftside 23 and the right side 24 between the first lug 27 and the secondlugs 28 and respectively coupled to the guiding slots 16 of the baseframe 10.

Referring to FIGS. 5 and 6 and FIGS. 1 and 2 again, the lockingmechanism 30 comprises a lock pin 32, a locating plate 33, and acompression spring 34. The lock pin 32 has a stop flange 35 protrudedfrom the periphery of the middle part. The locating plate 33 has acenter insertion hole 36, and two stop rods 37 perpendicularlysymmetrically extended from one side. The lock pin 32 is transverselyprovided at the front side of the base frame 10 and inserted through thecenter insertion hole 36 of the locating plate 13, having one endextended out of the base frame 10 and provided with a handle 31, and theother end inserted into the trough hole of the first lug 27 of thetreadmill frame. When pushing the lock pin 32 toward the inside of thebase frame 10 to force the stop flange 35 through the center insertionhole 36 of the locating plate 13, the lock pin 32 is engaged into thelug 14 of the base frame 10 and the through hole of the first lug 27 ofthe treadmill frame 20 to lock the front side of the treadmill frame 20to the base frame 10. On the contrary, when pulled the lock pin 32outwards and then rotated the lock pin 32 through an angle to disengagethe lock pin 32 from the lug 14 of the base frame 10 and the first lug27 of the treadmill frame 20 and to stop the stop flange 35 of the lockpin 32 against the stop rods 37 of the locating plate 33, the treadmillframe 20 is unlocked from the base frame 10. Further, the spring member34 is sleeved onto the lock pin 32 to push the lock pin 32 inwards fromthe unlocking position toward the locking position.

The two crank arms 40 are respectively pivoted to the rod 28 a that isconnected to the second lugs 28 of the treadmill frame 20, each having afirst segment 41 and a second segment 42 integrally extended from an endof the first segment 41 at an angle at an angle. The first segment 41has the distal end mounted with a sliding member, namely a roller 43,which is supported on the floor. Torsional springs 44 are respectivelysleeved onto the rod 28 a. The torsional spring 44 has a distal endfastened to the treadmill frame and the other distal end pressed on thefirst segment 41 of the crank arm 40 for imparting a downward force tothe first segment 41 of each crank arm 40 and an upward force to thetreadmill frame 20.

The lifting mechanism 50 is mounted in the treadmill frame 20,comprising a motor 51 and a transmission unit 52 driven by the motor 51.The output shaft 53 of the motor 51 is a screw rod extended in parallelto the length of the treadmill frame 20. The transmission unit 52 iscomprised of a sliding block 54 threaded onto the output shaft 53 of themotor 51, and two parallel links 55 pivotally connected to two lateralsides of the sliding block 54. The links 55 each have one endrespectively pivoted to the sliding block 54 and the other endrespectively pivoted to the distal ends of the second segments 42 of thecrank arms 40. During rotary motion of the output shaft 53 of the motor51, the sliding block 54 is forced to move along the output shaft 53,thereby causing the links 55 to move the crank arms 40, and thereforethe rollers 43 are moved forwards or backwards on the floor.

Referring to FIGS. 3 and 4, when wishing to increase the angle ofinclination of the treadmill frame 20, hold the handle 31 of the lockpin 32 with the hand and then pull the lock pin 32 outwards to unlockthe front side of the treadmill frame 20 from the base frame 10, andthen operate the control panel 13 to rotate the output shaft 53 of themotor 11 of the lifting mechanism 50 clockwise (viewed from the frontside of the treadmill frame 20), causing the slide 54 to move along theoutput shaft 53 toward the rear side 22 of the treadmill frame 20. Atthis time, the links 55 are forced to turn the crank arms 40 and to movethe rollers 43 on the floor toward the front side, and therefore thetreadmill frame 20 is turned about an axis passing through the footmember 26 to lift the front side 21 of the treadmill frame 20 from thebase frame 10 and the locating rods 29 are moved upwards along therespective guiding slots 16. When wishing to reduce the angle ofinclination of the treadmill frame 20, operate the control panel 138 torotate the output shaft 53 of the motor 51 of the lifting mechanism 50in counter-clockwise direction, thereby causing the sliding block 54 tomove along the output shaft 53 toward the front side 21 of the treadmillframe 20. At this time, the links 55 are forced to turn the crank arms40 and to move the rollers 43 on the floor toward the rear side, andtherefore the treadmill frame 20 is turned about an axis passing throughthe foot member 26 to lower the front side 21 of the treadmill frame 20to the base frame 10 and the locating rods 29 are moved downwards alongthe respective guiding slots 16.

When wishing to receive the treadmill frame 20, move the treadmill frame20 to horizontal according to the aforesaid angle of inclinationadjustment procedure, and then push the lock pin 32 toward the inside ofthe base frame 10 to lock the front side 21 of the treadmill frame 20 tothe base frame 10, and then operate the control panel 13 to rotate theoutput shaft 53 of the motor 51 of the lifting mechanism 50 in clockwisedirection and to further move the sliding block 54 along the outputshaft 53 toward the rear side 22 of the treadmill frame 20, therebycausing the links 55 to pull the second segments 42 of the crank arms40. At this time, the rollers 43 are moved on the floor toward the frontside, thereby causing the treadmill frame 20 to be turned about the lockpin 32 and to lift the rear side 22 of the treadmill frame 20 from thefloor, and therefore the treadmill frame 20 is received to the upright12 and held in the non-operative position. Because the sliding block 54is coupled to the output shaft 53 through screw joint, the output shaft53 can drive the sliding block 54 to move; however the sliding block 54cannot drive the output shaft 53 to rotate. This one-way self-lockingfunction prevents falling of the treadmill frame 20 accidentally duringlifting or receiving operation.

By means of the aforesaid design, the exercise treadmill can beelectrically controlled to adjust the angle of inclination andautomatically received in the non-operative position.

Although a particular embodiment of the invention has been described indetail for purposes of illustration, various modifications andenhancements may be made without departing from the spirit and scope ofthe invention. Accordingly, the invention is not to be limited except asby the appended claims.

1. An exercise treadmill comprising: a base frame for placing on afloor; a treadmill frame having a front side detachably connected withsaid base frame, and a rear side; a locking mechanism provided at afront side of said base frame for locking the front side of saidtreadmill frame to said base frame; at least one crank arm pivoted tosaid treadmill frame, said crank arm having a sliding member forsupporting on the floor; and a lifting mechanism mounted in saidtreadmill frame, said lifting mechanism including a motor, and atransmission unit coupled between said motor and said crank arm formoving said sliding member of said crank arm on the floor upon operationof said motor to either force the front side of said treadmill frame tomove vertically relative to said base frame while the front side of saidtreadmill is detached from the base frame or force the rear side of saidtreadmill frame to move vertically relative to said base frame while thefront side of said treadmill is locked to the base frame by the lockingmechanism.
 2. The exercise treadmill as claimed in claim 1, wherein saidtransmission unit comprises a sliding block coupled to said motor andforwardly backwardly movable by said motor in direction between thefront side and rear side of treadmill frame, and at least one linkpivotally coupled between said sliding block and said at least one crankarm.
 3. The exercise treadmill as claimed in claim 1, wherein saidlocking mechanism comprises a locating plate affixed to said base frame,said locating plate having a center insertion hole and at least one stoprod protruded from a side thereof, a lock pin inserted through thecenter insertion slot of said locating plate and movable between a firstposition where said lock pin is engaged into a part of the front side ofsaid treadmill frame to lock the front side of said treadmill frame tosaid base frame and a second position where said lock pin is disengagedfrom the front side of said treadmill frame to unlock the front side ofsaid treadmill frame from said base frame, said lock pin having a stopflange, which is moved through the center insertion hole of saidlocating plate when said lock pin is set in said first position, orstopped against said at least one stop rod to hold said lock pin in saidsecond position after said lock pin has been disengaged from the frontside of said treadmill frame and rotated relative to said locating platethrough an angle.
 4. The exercise treadmill as claimed in claim 1,further comprising at least one torsional spring having a distal endconnected to said crank arm and the other distal end connected to saidtreadmill frame.
 5. The exercise treadmill as claimed in claim 1,wherein said base frame comprises two upright sidewalls symmetricallydisposed at two opposite lateral sides thereof, said upright sidewallseach having a vertically extended guiding slot and a sliding slothorizontally forwardly extended from a bottom end of said guiding slot;said treadmill frame comprises two locating rods respectively protrudedfrom two opposite lateral sides thereof and respectively coupled to theguiding slots of said upright sidewalls and movable between the guidingslots and sliding slots of said upright sidewalls.